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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Single phase grid tie inverter for solar PV panels with active power decoupling circuit

Ramasubramanian, Karthik 13 August 2012 (has links)
Distributed energy resources like solar power (PV Panels) are usually connected to the AC grid through a single phase voltage source inverter (VSI). The major drawback associated with single phase grid tie inverters is the double frequency component of the grid that appears on the DC bus link. Large electrolytic capacitors are generally employed in the inverters to eliminate the ripple component. However, their bulkiness and relatively short lifetime are motivational factors to replace them with small film capacitors. This paper presents a synchronous boost/buck based active power decoupling circuit in parallel with the dc-bus link capacitor and discusses the different types of control strategies implemented. Simulation results are presented for each control technique and it is shown that the ripple on the DC bus link is largely reduced due to inclusion of this circuit along with an expected extension of the lifetime due to the reduction in the amount of dc-bus capacitance used. / text
2

Evolutionary Optimization Applied to Usage of Solar Energy for Powering a Heat Pump

Thomasson, Henrik January 2021 (has links)
This paper researches the impact of different settings on an Infinite Impulse Response-filter (IIR-filter) used on a NIBE heat pump in combination with photovoltaic panels (PV-panel). The IIR-filter is applied to the level of the PV-panel’s power and its output is used by the heat pump’s control to harvest as much solar power as possible for supplying the heat pump with electricity. In some of the experiments weather data is used in the form of a forecast regarding the incoming cloudiness in the area, called “cloud coverage”. My objective is to find out which setting performs the best, and whether an evolutionary algorithm can find an optimal setting. The evolutionary algorithms I try are Genetic Algorithm, Simulated Annealing and the Hill Climbing algorithm. Historical data is collected from one of NIBE’s active heat pumps running in a field test. The data is processed and experimented on using an algorithm that analyzes how close a certain setting of values for the coefficient used in the filter and sensitivity of the cloud coverage forecast performs compared to an ideal reference. By using an evolutionary algorithm a better solution to the usage of solar energy can be found, compared to the non-evolutionary algorithm, by using a combination of different values for the coefficient in the filter, and also the cloud coverage forecast, which decides when we should change to another value for the filter coefficient.
3

Study of Energy Neutrality in Kochi Metro Rail, India

Paul, Jeena January 2021 (has links)
Now a days, the society thinks about more sustainable and clean energy sources. Most of the countries in the world relay on non-renewable energy sources for the generation of electricity. This results in the scarcity of fossil fuels in future and also increases the production of carbon emissions. This thesis considers a metro system named Kochi Metro which is a rapid transit system serving in the city of Kochi in Kerala, India which uses renewable sources, mainly solar, for giving power to the Metro.In this thesis work, trying to analyze the measures adopted by Kochi Metro Rail project in potential reductions of energy consumption and energy generation both contributing to energy efficiency.With the help of Matlab, different levels of installed PV power are used to find out the possible self-usage, self-sufficiency, and energy neutrality of the system.
4

Application of PV Panels in Large Multi-Story Buildings

Kayal, Sara 01 June 2009 (has links) (PDF)
Application of PV Panels in Large Multi-Story Buildings Feasibility Study Sara Kayal The awareness of global warming along with an ever increasing demand for a new source of energy has brought a strong interest in harnessing natural resources such as solar energy. This thesis evaluates the viability of applying photovoltaic (PV) panels in high-rise commercial buildings of around 20 stories. Specifically, the thesis is intended to provide a pre-planning tool during the early design stage for architects and designers who are considering the deployment of PV panels in new multi-story construction. The first three chapters cover a comprehensive literature review and describe several case studies of the application of PV panels in multi-story buildings. The first chapter serves as an introduction to the objectives and rationale of PV panel research. Chapter 2 explains the physics and characteristics of PV panel technology that is applicable to multi-story buildings. Various PV panel types are explored in this chapter and it is suggested that window-based PV panels are the most suitable type for multi-story buildings in which the available roof area is small in area and limited in flexibility due to competition with other uses. Chapter 3 investigates factors that influence the efficiency of PV panels. These factors reduce the efficiency of PV panels to about 10-15%. In Chapter 4 a study model is presented to validate the results of the previous chapters and to determine the feasibility of PV panel systems with the aid of computer model analysis and simulation. The study model includes a base case of a 20-story building that is surrounded by four adjacent buildings, one adjacent to each orientation. Five configurations of the base model with different arrangements of PV panels were analyzed. First, electrical energy of the base case was calculated without applying any PV panels. The second and third configurations include PV panels on all of the available façade areas on a typical summer and winter day, respectively. The fourth and fifth configurations feature PV panels on only the top 10 floors. The simulation results show that although some savings accrue over a 25-year life-cycle period, these savings pale in comparison with the initial capital cost associated with the purchase and installation of the PV panels. It was also found that although crystalline silicon panels have a higher initial cost, their superior efficiency and performance present them as better candidates for PV panel applications. In addition, as expected, the south orientation provides potentially the largest amount of electricity production. In Chapter 5 the simulation results are summarized. The simulation studies address the application of PV panels from three different perspectives, namely: economics; technical feasibility; and, subjective factors. The first four chapters confirm that PV panels, at the current level of technology, are not an efficient and cost effective solution for multi-story buildings. They can satisfy only a very small portion of the electrical energy demand of the building at a very high initial capital cost. However, some strategies are suggested for mitigating the dual problems of inadequate PV production volume and high initial costs. Subjective factors account for other benefits that are not related to economic considerations. These factors include educational, promotional, and business line promotion benefits that could accrue to the building owner.
5

Development of Photovoltaic System Simulator : PV Remote Lab

Querol Puchal, Jesus January 2024 (has links)
Currently, a sustainable energy transition is underway to reduce CO2 emissions. To meet the targets outlined in international agreements like the Kyoto Protocol, a rapid expansion of renewable energy sources, particularly photovoltaic (PV) systems, is underway. Due to photovoltaic technology's rapid development and integration, reliable testing and evaluation methods are essential. This master's thesis is dedicated to developing a PV system simulator to study the PV systems. PV simulators serve as precious tools due to their capacity to control and replicate the environmental conditions experienced by PV panels. Consequently, these simulators facilitate thorough research, design refinement, and PV system performance assessment. The developed PV system simulator is essentially a PV remote lab, offering the capability to monitor, gather data, and evaluate the performance of the PV system remotely. The proposed system's flexibility and scalability enable its application to study various types of PV installation. The PV remote lab is expected to be a training centre for students and industry professionals. A comprehensive literature review on photovoltaic technology has been undertaken. Following the literature review, the different components that form a PV system have been defined and selected. The system will have a communication block to achieve a flexible and scalable PV remote lab. In this way, different configurations of the PV panels and different system outputs can be implemented. This commutation block can be remotely controlled using an Arduino, and an interface can be designed where the desired PV panel configurations and system outputs can be selected. In this interface, visualising the tests' results will also be possible. / För närvarande pågår en hållbar energiomställning för att minska koldioxidutsläppen. För att uppfylla de mål som fastställts i internationella avtal som Kyotoprotokollet pågår en snabb utbyggnad av förnybara energikällor, särskilt solcellssystem (PV). På grund av solcellsteknikens snabba utveckling och integration är tillförlitliga test- och utvärderingsmetoder av avgörande betydelse. Denna masteruppsats handlar om att utveckla en solcellssimulator för att studera solcellssystem. PV-simulatorer är värdefulla verktyg eftersom de kan kontrollera och återskapa de miljöförhållanden som PV-panelerna utsätts för. Följaktligen underlättar dessa simulatorer grundlig forskning, designförbättring och bedömning av PV-systemets prestanda. Den utvecklade PV-systemsimulatorn är i grunden ett fjärrstyrt PV-labb som gör det möjligt att övervaka, samla in data och utvärdera PV-systemets prestanda på distans. Det föreslagna systemets flexibilitet och skalbarhet gör att det kan användas för att studera olika typer av solcellsinstallationer. PV-fjärrlabbet förväntas bli ett utbildningscenter för studenter och yrkesverksamma inom branschen. En omfattande litteraturgenomgång om solcellsteknik har genomförts. Efter litteraturgenomgången har de olika komponenterna som bildar ett solcellssystem definierats och valts ut. Systemet kommer att ha ett kommunikationsblock för att uppnå ett flexibelt och skalbart PV-fjärrlabb. På så sätt kan olika konfigurationer av solcellspanelerna och olika systemutgångar implementeras. Detta kommutationsblock kan fjärrstyras med en Arduino och ett gränssnitt kan utformas där de önskade konfigurationerna av solcellspaneler och systemutgångar kan väljas. I detta gränssnitt kommer det också att vara möjligt att visualisera testresultaten.
6

SELF-SUFFICIENT OFF-GRID ENERGY SYSTEM FOR A ROWHOUSE USING PHOTOVOLTAIC PANELS COMBINED WITH HYDROGEN SYSTEM : Master thesis in energy system

Maxamhud, Mahamed, Shanshal, Arkam January 2020 (has links)
It is known that Sweden is categorised by being one of the regions that experience low solar radiation because it is located in the northern hemisphere that has a low potential of solar radiation during the colder seasons. The government of Sweden aim to promote a more sustainable future by applying more renewable initiative in the energy sector. One of the initiatives is by applying more renewable energy where PV panels will play a greater role in our society and in the energy sector. However, the produced energy from the PV panels is unpredictable due to changes in radiation throughout the day. One great way to tackle this issue is by combining PV panels with different energy storage system. This thesis evaluates an off-grid rowhouse in Eskilstuna Sweden where the PV panels are combined with a heat pump, thermal storage tank, including batteries and hydrogen system. The yearly electrical demand is met by utilizing PV panels, battery system for short term usage and hydrogen system for long-term usage during the colder seasons. The yearly thermal demand is met by the thermal storage tank. The thermal storage tank is charged by heat losses from the hydrogen system and thermal energy from heat pump.The calculations were simulated in Excel and MATLAB where OPTI-CE is composed with different components in the energy system. Furthermore, the off-grid household was evaluated from an economic outlook with respect to today’s market including the potential price decrease in 2030.The results indicated that the selected household is technically practicable to produce enough energy. The PV panels produces 13 560 kWh annually where the total electrical demand reaches 6 125 kWh yearly (including required electricity for the heat pump). The annual energy demand in terms of electricity and thermal heat reaches 12 500 kWh which is covered by the simulated energy system. The overproduction is stored in the batteries and hydrogen storage for later use. The back-up diesel generator does not need to operate, indicating that energy system supplies enough energy for the off-grid household. The thermal storage tank stores enough thermal energy regarding to the thermal load and stores most of the heat during the summer when there are high heat losses due to the charge of the hydrogen system. The simulated energy system has a life cycle cost reaching approximately k$318 with a total lifetime of 25 years. A similar off-grid system has the potential to reduce the life cycle cost to k$195 if the energy system is built in 2030 with a similar lifespan. The reduction occurs due to the potential price reduction for different components utilized in the energy system.
7

Montagekvalité av solcellsinstallationer i Mellansverige : En utvärdering av hållfasthet för installerade solcellsanläggningar

Nyman, Joar January 2020 (has links)
Antal installerade solcellsanläggningar har ökat drastiskt de senaste åren i Sverige, och utsikten för ökad mängd solel i Sverige är mycket god, med prognoser på kraftig tillväxt av installerade solcellsanläggningar de kommande åren. Detta med bakgrund att utvecklingen av solcellspaneler har gjort att priset har sjunkit, samt politiska beslut har gjort det lönsamt att investera i solcellsanläggningar i Sverige. Dessa förutsättningar har lagt grunden för en ny växande bransch, solcellsinstallationer. Risken vid en ny och snabbt växande bransch är att kunskapen inom ämnet för de som är verksamma inom branschen kan vara bristfällig samt oseriösa företag kan lockas av att tjäna snabba pengar på en lukrativ marknad. Efter en omfattande litteraturstudie visades att någon större kvalitésundersökning av solcellsinstallationer i Sverige, med avseende på hållfasthet ej har gjorts tidigare. Detta motiverade att denna undersökning var av hög relevans. Syftet med denna studie var att ta reda på om solcellsanläggningar monteras tillräckligt hållfast i Gävle-Dalaregionen med avseende på snö- och vindlast. Fjorton anläggningar har besökts för att samla in data. Data har sedan utvärderats i tre kategorier per anläggning. För att en anläggning skall bedömas som en godkänd skall alla dessa tre kategorier vara godkända. Bedömningen av solcellsanläggningarna gjordes i de tre kategorierna: 1. montagesystemets antal infästningar, 2. mått mellan infästningarna, 3. placering av solcellspanelerna i förhållande till montagesystemet. Resultatet visade att ingen av dessa anläggningar var godkända i samtliga tre kategorier. Vissa anläggningar var godkända i två av tre kategorier, medan två anläggningar var ej godkänd i någon kategori. Vid en summering av bedömningsresultatet för alla anläggningar i de tre montagekategorierna, visades att ca 20% ej gick att fastställa (pga. bristande information) ca 40% var godkända och ca 40% var ej godkända. Bedömningar har gjorts utifrån beräkningsprogram och anvisningar tillhandahållna av tillverkarna av de montagesystem och solcellspaneler som har använts i anläggningarna. Att ingen anläggning var godkänd i samtliga tre kategorier som undersöktes indikerar att solcellsmontage på tegeltak byggs ej tillräckligt hållfast i Gävle-Dalaregionen. Detta kan dock inte generaliseras för solcellsanläggningar på tegeltak i hela Sverige då mängden undersökta anläggningar var relativt liten och endast fördelade på två län i landet. Då det antas att installatörer avser att bygga korrekta anläggningar visar denna studie att kunskap om solcellsmontage med avseende på hållfasthet är bristfällig. Detta kan vara en följd av den stora efterfrågan på solcellsinstallationer, som kan medföra att stort fokus ligger på att installera anläggningar snabbt, och inhämtning av kunskap ej blir prioriterat. / The number of installed PV-systems (Photovoltaic systems) has increased rapidly in Sweden the last years, and the forecast for even more installations shows an increase for the coming years. Due to the price for PV-panels har dropped and political decisions for subventions of PV-systems has made it more profitable to invest in PV-installations in Sweden. These reasons have paved the road for a new growing branch, PV-installations. The risk of a new profitable, fast growing branch is that there might be short of knowledge for new installers, and the possibility that dishonest companies just want to take the advantage of the situation to make quick money, which can lead to installations poorly made.   After a search of published literature in strength of mounting for PV-panels there the result was that this is a rather unexplored subject, which motivated this investigation.   The aim of this study was to find out if PV-panels on tiled roofs were installed correct due to the snow load and wind load in the region Dalarna and Gävleborg in Sweden.   Fourteen PV-systems has been studied and evaluated. When the evaluation of the PV-systems were made the following criteria were considered: number of fixing attached to the roof of the mounting, distance between mounting fixings and how the PV-panels were installed relative the construction of the mounting. A PV-system had to be installed correctly for all three criterias to be considered approved. The result of this work shows that none of the evaluated systems were installed correctly. Some systems were approved in two of the criteria, while two systems were not approved in any of the criteria. The evaluation was made due to calculation programs and instructions from the manufacturers of mounting and PV-panels.   The fact that none of the PV-systems were approved for all three criteria implies that the installations of PV-systems are not made strong enough. This result is not stated for all installations in Sweden because the number of studied PV-systems were not big enough, and the area of the studied installations were rather small. Basis of snow load and wind load variates quite much in Sweden depending on region. It is assumed that designers and constructors attempt to install PV-systems correct, therefor shows this work that there’s a lack of knowledge for construct installations strong enough. This may be a result of the fast increase of PV-installations, where the priority lays in installing many PV-systems, not in education and search of knowledge.
8

Recycling Waste Solar Panels (c-Si & CdTe) in Sweden

Nekouaslazadeh, Alireza January 2021 (has links)
Solar energy industries are one of the fastest-growing industries in the global energy market. Between 2018 and 2019, installed capacity in Sweden increased by 70%. This is due to a combination of declining PV module and inverter costs, as well as  increased conversion to fossil-free energy production to mitigate greenhouse gas emissions. In fact, solar PVs have a 25-year life span, and soon many deployed PVs would soon reach their end of life (EoL), it is, therefore, important to organize for the EoL of PVs in order to recover precious resources and recycle PV modules in a sustainable manner. Currently, less than 10% of global solar cell waste is recycled, due to the lack of incentives for recycling in most countries. In the European Union, used-up modules are governed by the WEEE (Waste Electrical and Electronic Equipment) Directive, which requires the collection of 85% of solar cell waste, with at least 80% of the waste being prepared for reuse or recycling. Solar cell waste has not amounted to significant volumes in Sweden, due to the lack of no known systems for recycling. Used-up modules are currently collected and managed as electronic waste in one of two approved collection systems in Sweden. The aim of this thesis is to analyze and assess methods of recycling waste solar panels in Sweden and is it economically viable to set up a solar waste recycling center before it reaches the right amount of waste. Moreover, the main focus is on the analysis and comparison of the environmental impacts of various recycling methods for crystalline silicon (c-Si) and cadmium telluride (CdTe) panels. To recycle solar panel waste, the elements of these panels must be assessed from both an economic point of view as well as environmental impacts. Today, the most common PV panels in the global market and also Sweden are c-Si and CdTe types. The results showed except for the pyrolysis method, the environmental impacts of both c-Si and CdTe PV panels from the thermal-based recycling methods, are lower than chemical methods. Furthermore, the extraction of Al, Si, and glass from c-Si and the extraction of glass from CdTe has a less environmental impact than the current techniques used in the recycling of PV panels. Finally, in this study, we revealed which materials can be prioritized for maximum economic and environmental advantages from recycling. In c-Si modules, these are Ag, Al, Si, and glass and in CdTe modules, these are Te, Cu, and glass. Currently, investing in a new solar module recycling center in Sweden is not economically viable. Because the possibility of such an investment requires economic and political incentives. Given that by 2042 the volume of Swedish solar waste will not reach the minimum level of profitability to build a new specialized center for the recycling of solar modules, the best decision is to modify the existing plants in Sweden to recover expensive and vital materials.
9

Modélisation, commande et supervision d'un système multi-sources connecté au réseau avec stockage tampon de l'énergie électrique via le vecteur hydrogène / Modelling, control and supervision of multi-source system connected to the network with a buffer storage of electrical energy via hydrogen vector

Tabanjat, Abdulkader 25 September 2015 (has links)
Les réserves limitées de combustibles fossiles et la pollution entrainée par les gaz produits ouvrent la voie à desressources énergétiques renouvelables (RER) alternatives et prometteuses telles que les ressources solaires (RS)et les ressources éoliennes (RE). Ces ressources sont librement disponibles et respectueuses de l'environnement.Cependant, les RER sont de nature intermittente. Par conséquent, il existe un besoin de lissage des fluctuations depuissance en stockant l'énergie pendant les périodes de surproduction pour la restituer au réseau lorsque lademande énergétique devient importante. Les systèmes de stockage de l'énergie (SSE) peuvent alors être utilisésde manière appropriée à cette fin.L'utilisation de plusieurs sources d'énergie et de stockeurs pour construire des systèmes de puissance hybrides(SPH) exige une stratégie de gestion de l'énergie pour atteindre le minimum de coût des SPH et un équilibre entrela production et la consommation de l'énergie. Cette méthode de gestion de l'énergie est un mécanisme pourobtenir une production d'énergie idéale et pour satisfaire convenablement la demande de charge à rendementrelativement élevé.Dans cette thèse, un SPH intégrant production électrique photovoltaïque, éolienne, une micro-turbine à gaz ainsiqu'un système de stockage de l'électricité par le vecteur hydrogène est considéré. Le but de cette hybridation estde construire un système fiable, qui est en mesure de fournir la charge et qui a la capacité de stocker l'énergieexcédentaire sous forme hydrogène et de la réutiliser plus tard. En outre, le problème d'ombrage partiel dePanneaux Photovoltaïques est étudié de manière approfondie. Une nouvelle solution basée sur des interrupteurssimples et un contrôle par logique floue intégré dans une carte électronique dSPACE a été proposée. Unereconfiguration des panneaux photovoltaïques en temps réel et de déconnexion de ceux ombragés est égalementeffectuée en cherchant à minimiser les pertes de puissance. Le couplage thermique entre ces panneauxphotovoltaïques et un électrolyseur à membrane polymère est également étudié, à l'échelle système. Enrécupérant une partie de l'énergie thermique reçue par les panneaux, une amélioration du rendement du systèmehybride PPVELS MEP est réalisée / The limited reserves of fossil fuel and the pollution gases produced pave the way to promising alternativeRenewable Energy Sources (RESs) such as Solar Energy Sources (SESs) and Wind Energy Sources (WESs).SESs and WESs are freely available and environmentally friendly. However, RESs are intermittent in nature.Therefore, the smoothing of power fluctuations by storing the energy during periods of oversupply and restore it tothe grid when demand becomes necessary. Accordingly, Energy Storage Systems (ESSs) can be appropriatelyused for this purpose.Using several energy sources for constructing HPSs alongside with ESS will require an energy managementstrategy to achieve minimum HPS cost and optimal balance between energy generation and energy consumption.This energy management method is a mechanism to achieve an ideal energy production and to conveniently satisfythe load demand at relatively high efficiency.In this thesis, a Hybrid Power System (HPS) including Renewable Energy Sources (RESs) such as main sourcescombined with Gas Micro-Turbine (GMT) and hydrogen storage system such as Back-up Sources (BKUSs) hasbeen presented. The aim of this hybridization is to build a reliable system, which is able to supply the load andhaving the ability to store the excess energy in hydrogen form and reuse it later when demanded. Consequently, thestored energy at the end of each cycle will be zero and a minimum generated power cost is achieved. In addition,partial shading problem of Photovoltaic (PV) panels is comprehensively studied and a new solution based on simpleswitches and Fuzzy Logic Control (FLC) integrated into dSPACE electronic card is created. Consequently, a realtime PV panels reconfiguration and disconnecting shaded ones is performed and minimum power losses isachieved. Then, the PV panels are connected to a Proton Exchange Membrane Electrolyser (PEM ELS). Theemitted temperature by the PV panels is transferred to the endothermic element PEM ELS. Consequently, anefficiency enhancement of the hybrid system PVPEM ELS is realized.

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